In　this　paper,　we　study　the　Bogdanov-Takens　singularity　in　the　Hindmarsh-Rose　neuron　model　with　time　delay.　We　use　the　center　manifold　reduction　and　the　normal　form　method,　by　means　of　which　the　dynamics　near　this　nonhyperbolic　equilibrium　can　be　reduced　to　the　study　of　the　dynamics　of　the　corresponding　normal　form　restricted　to　the　associated　two-dimensional　center　manifold.　We　show　that　changes　in　the　time　delay　length　can　lead　to　the　saddle-node　bifurcation,　to　the　Hopf　bifurcation,　and　to　the　homoclinic　bifurcation.　(C)　2019　Elsevier　Inc.　All　rights　reserved.